1. Field of the Invention
This invention relates to information technology (IT), and more particularly, to a computer platform system power state management method and system which is designed for use in conjunction with a computer platform, such a network server, a desktop computer, or a notebook computer, for providing the computer platform with an after-G3 (i.e., restoration of power after abnormal interruption) system power state management function that allows the computer platform's system power state to be automatically restored to the original state prior to the power interruption.
2. Description of Related Art
ACPI (Advanced Configuration and Power Interface) is a high-performance computer configuration and power management technology which is now widely utilized on various types of computer platforms, including network servers, desktop computers, and notebook computers, for efficient power management on the computer platform.
For power management, the ACPI specification sets forth 4 global states (respectively denoted by G0, G1, G2, and G3) and 6 system power states (respectively denoted by S0, S1, S2, S3, S4, and S5). In particular, the G3 global state is used to represent that the computer platform is currently inoperable due to power interrupt or shutoff, and the system power states S0, S1, S2, S3, S4, and S5 are used to represent the following conditions:
S0: On
S1: Power On Suspend
S2: Pseudo-Suspend to RAM
S3: Suspend to RAM
S4: Suspend to Disk (Hibernate)
S5: Soft off
Since ACPI is a well-known standard in the computer industry, detailed descriptions about these states G3 and S0-S5 can be found in the ACPI specification so that details thereof will not be given in this specification.
During operation of a computer platform, if a power interruption occurs due to a failure in the power supply or user-intended shutoff, the computer platform's ACPI global state will be set to G3. When power restores to the computer platform after the G3 power interruption, it is required to reset the computer platform's system power state to the original state prior to the power interruption. In the document, the system power state after power restoration is technically referred to as“After G3” state. For example, if the computer platform is set in (S0, S1) system power state when the G3 condition occurs, then after power restoration, the computer platform should be set to (S0); and on the other hand, if the computer platform is set in (S4, S5) when the G3 condition occurs, then after power restoration, the computer platform should be set to (S4, S5).
A conventional method for setting after-G3 system power state is to utilize a BMC (Baseboard Management Controller) module or an SIO (Super Input/Output) module installed in the computer platform to perform an after-G3 system power state resetting procedure for resetting the computer platform's after-G3 system power state to the original state after abnormal power interruption.
One drawback to the above-mentioned method, however, is that it is only suitable for use on computer platforms equipped with BMC and SIO (which are typically high-end network servers), and unsuitable for use on low-end computer platforms that are unequipped with BMC and SIO.